Forcing others to become a Muslim is forbidden in Islam.
As someone else said, you've only seen the extremists and not the good ones. Go to Saudi Arabia, there are tons of good Muslims out there. If you see some guy who kills people and calls himself a Muslim, would you believe him? There are some rules Muslims need to follow.
Still some radical groups always do what states that is forbidden by "the Qu'ran.
I know alot of good muslims and they also have nice parents and always are respectful to me.













